Prince Philip ascended inside the curved-glass pod, which gives a 360-degree view of up to 26 miles of the south coast. The duke was shown the control room and the operating winch, before unveiling a plaque.

The i360 holds the Guinness World Record for the globe's most slender tower, with a diameter of 3.9m at its widest point.

Meanwhile, his grandson, Prince Harry, is in Malawi, where he said the experience of helping to move African elephants across Malawi was "amazing".

He spent three weeks in Malawi in July and August working on a major project to transfer 500 elephants more than 200 miles to a wildlife reserve.